Process of making arsenates of manganese



nomical process 6 atlvely plentiful "of manganese and arsenic, manganese reacting upon manga 1 arsemc acid and also as 1 nonoxidizing ganese such as higher oxids of m Mn,,O and 'MnO part, upon and arsenious and arsenic for that ,v oxid, althoug ing bination of manganese O S oxid could be completion or substantial comple Patented July 6, 192s.

' umrso STA l TANNEB, OF CLEVELAND, OHIO, CHEMICAL COIPANY, OF CLEVELAND, OHIO A CORP wnnnmeron LEE rss PATENT orrics."

assrenoa 'ro THE ea'assnr'mr.

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10 Drawing. Application filed July 30,

This invention relates to a process of making arsenates of manganese, particularly to. the provision of oxid and arsenious oxid.

Arsenates. of manganese can be acting upon manganese monoxid senic oxid arsenates of manganese may arsenious oxid by treating compound agent nitric acid, or by treating oxid with an-oxidizing success of the last mentioned sumably depending wholly,

the mutual and senic oxid or 'lbS theoretical the reduction of the manganese. to lent atom. From the 30 ical commercial manufacture of the use of manganese oxid of course is preferred, since these two compounds offer the cheapsources of manganesepurpose at the present of manganese est and most plentiful time, and theinvention will be and. illustrated the process of making nese from manganese dioxid and itis to be understood that the ventionembraces the other novel combinareferred to.

and arsenious together in the presence 0 combination takes place,

tions of reagents heretofore When manganese dioxid complete to.

commercially practicable manner, of a varietyp involving the use of the reland inexpensive sources nese carbonate wit I have found by reor acid. I have now found that be made from the same with a of manganese, such as the monoxid or carbonate in the compound of manmanganese nitrate or the anganese such as 2 or mixtures thereof, he

reactions preor at least in simultaneous OXldittlOII of the arsenious oxid to the arequivalent and standpoint of economhereinafter by reference to arsenates of mangaf catalytic or accelerating agents was tried with varying success. ,The

1923', Serial m. 654,781. Renewed November 12,1925.

and more an ecomay be used, in general,

of compound with manganese. stances of tioned nitric acid, nitrobenzene, acetic acid, formic sulfonic acid products made b with arof a catalytic agent of a catalytic agent the reaction in the agent, therefore, is tion.

such as arsemous will be pointed out hereinafter.

. The following is a. description of ferred procedure in vention, which will 261 parts by dioxid containing the diva-s ganese dioxid ore,

arsenates (white arsenic) or dioxid heated to a temperature 0 1n, for instance, described eted vessel an to maintain the pasty condition.

- arsenious arsenious oxid given are results, and the workability or toc =nstandpoint ofeconomy in acid and reaction rate, due evaporation of the liquid the mixture. substantially complete 1 reaction place in' about three'hours.

tion in a the effect.

results of these experiments clearly indicated thatas catalytic or accelerating agents substances capable forming an easily dissociable or labile Among subthis general class may be menpicric acid, aid, hydrofluosilicic acid, of hydrocarbons, and metal 'nitrates, such as manganese nitrate and the alkali and alkaline earth metal nitrates. As is indicated therefore the use 1 for the reaction is preferred,lalthough, asstated, manganese oxid and arsemous oxid react in the absence and the carrying out of absence of a catalytic embraced bythe inven- Further characteristics of the invention a P accordance with my 111- serve to illustrate it.

weight of manganese dioxid or an equivalent quantity of a manganese material, such as a manor concentrate, is mixe with 198 parts by weight or arsenious oxid equivalent quantity of an arsenious oxid containing material, 160 "parts by weight of water, and 12 parts by weight of nitric acid, and the mixture is f say 80 to C. a hot water or steam jackd stirred or agitated, water being added from time to time, if necessary, mixture in, a moist and The proportions of manganese dioxid and the theoretical proportions, the quantity of 'quantity'of nitric acid is the best from the I the use of nitric and the temperature is highest temperature usable without unntent of Under theconditions stated,

' take the nitric acid.

manganese dioxid and arsenious oxid other than those given in the foregoing example. The quantity of water used in the reaction mixture may be varied, but in this connection it is noted that the reaction is much slower or does nottake place at all if the mixture is too dry, and iftoo much water is used, for instan'ce,'a quantity sufiicient to make a thin slurry, the reaction rate is retarded. The quantity of nitric acid in the reaction mixture may also be varied. If, for instance, the quantity of nitric acid in the reaction the reaction rate is greatly reduced, while the use of more nitric acid does not give a corresponding increase in the reaction rate. In general the higher the temperature to which the reaction mixture is heated, the greater is the reaction rate and the carrying out of the process under superatmospheric pressure in order to make possible the employment of highs; temperatures therefore is contemp ate Oxids of manganese other than MnO to wit, M11 0, and Mn O or mixtures thereof may replace wholly, or in part, the manganesfe dioxid in the foregoing example.

As has already been stated, a variety of catalytic or accelerating agents may be used, or instance in the example, the twelve parts by weight of nitric acid may be replaced by an equal weight of nitrobenzene, the' results being substantially the same as with When for instance acetic acid or formic acid is substituted for the nitric acid in the example, the reaction is accelerated, but the results are not so good,

the reaction rate'being considerably slower than when the nitric acid is used.

The product may be marketed directly in the pasty condition in which it is produced, or it may be und and then dried, or the paste ma be ried and then ground, as preferred. he product in view of-its arsenic content suggests itself as being a valuable material for ,use as or in insecticides.

In the appended claims I have defined the interaction of arsenious acid with a manganese compound capable of oxidiz' arsenious acid under which of course are included manganese nitrate and the higher oxids of manganese.

It is also to be understood that the claims cover not only the use of such oxidizing comounds of manganese as starting materials,

at also the use as starting materials of reagents capable of forming or having the same effect as the oxidizing compounds of manganese such as for instance, the use of a non-oxidizing compound of manganese in conjunction with an oxidizing agent.

mixture is reduced by one half,

I claim 1. Process of making manganese arsenates which comprises heating to reacting temperature a mixture of a compound of manganese capable of oxidizing arsenious oxid with arsenious oxid in the presence of water.

2. Process of making manganese arsenates which comprises heating to reacting temperature a mixture of a hi her oxid of manganese than the monoxid with aisenious oxid in the presence of water. i

3. Process of making manganese arsenates which comprises heating to reacting temperature a mixture of a higher oxid of manganese than the monoxid with arsenious oxid 1n the presence of water and a catalyticagent. 7

4. Process of making manganese arsenates which comprises heating to reacting temperature a mixture of a higher oxid of manganese than the monoxid with arsenious oxid in the presence of water and a substance capable of forming with manganese an easily dissociable product.

5. Process of makin manganese arsenates which comprises heating to reacting temperature a mixture of a higher oxid of manganese than the monoxid with arsenious oxid 1n the presence of water and nitric acid.

6. Process of makin manganese arsenates which comprises heatm to reacting temperature a mixture containing a higher oxid of manganese than the monoxid with arsenione oxid and water in "quantity s'ufiicient to form a pasty mass and a catalytic agent.

7. Process as defined in claim 6 in which the catalytic agent em loyed is nitric acid.

8. Process as define in claim 6 in which the oxid of manganese employed is manganese dioxid.

9. Process of making an arsenate of manganese which comprises heating to reacting temperature a mixture comprising about 261 parts by weight of manganese dioxid, 198 parts by weight of arsemous oxid, 160 parts by weight of water and 12 parts by weight of nitric acid, agitating the mixture during the heating operation and adding water as required to maintain the consistency thereof.

10. Process of making manganese arsenates which comprises heating to reacting temperature a mixture of an oxy compoun of manganese and arsenious oxid in the presence of an oxidizing agent capable of oxidizing arsenious arsemc to arsenic arsenic and water.

In testimony whereof, I afiix my signature. 

